YEREVAN -- Two members of the opposition Zharangutiun (Heritage) party have expressed concern over Armenia's new military accord with Russia, RFE/RL's Armenian Service reports.

They question Armenian officials' claims that the deal commits Russia to openly side with Armenia in the event of another war with Azerbaijan over the disputed territory of Nagorno-Karabakh. They also denounced Moscow's reported plans to sell sophisticated S-300 antiaircraft missiles to Azerbaijan.

Zharangutiun Deputy Chairman Ruben Hakobian said it was unclear whether and how the new agreement, signed last week, contributes to Karabakh's security.

Both Hakobian and Stepan Safarian, who heads Zharangutiun's parliament faction, also questioned the rationale for extending until 2044 the lease on the Russian base, which was due to expire in 2020. "This is not in Armenia's interests," Safarian argued.

The Armenian National Congress (HAK), a larger and more influential opposition force, similarly claimed on August 23 that the Kremlin moved to prolong the Russian military presence in Armenia because it did not regard the administration of President Serzh Sarkisian as a "long-term and reliable partner."

Nonetheless, the HAK's reaction to the Russian-Armenian deal was largely positive.

Like the HAK, the Zharangutiun leaders expressed serious concern at reports about the planned sale of Russian S-300 air-defense systems to Azerbaijan. They said Armenia should consider pulling out of the Russian-led Collective Security Treaty Organization (CSTO) if the deal goes through.